Most satellites which operate in earth orbit require some form of enriconmental control to maintain a thermal balance between the satellite components and the extremes of the low temperature space background and the radiative flux from the sun. These satellites employ a variety of standard techniques including thermal control coatings, radiators and multilayer insulation (MLI) to achieve this thermal balance. These thermal control systems utilize a variety of materials depending upon application and configuration but they generally have similar properties of lightweight, low outgassing, and high UV stability. Consequently, most of the subsystems have not been designed with any need for very high temperature stability.
Rigid low-density ceramic insulation can be used in areas requiring structural support over a span where flexible insulating materials may cause dynamic load or flutter problems. The insulation characteristic of rigid insulation foams is proportional to thickness. Rigid foam can never completely replace multilayer insulation because to have equal insulation capability, the thickness of such rigid foam must be quite large. There are, however, areas of space vehicles having complex contours that are difficult to wrap using the multilayer insulation, where the rigid foam may be molded to fit.
With the advent of ground and spaceborne High Energy Laser (HEL) threats, most of the standard materials and techniques commonly used become vulnerable to severe degradation resulting from the high flux and fluence levels. As a result, active and passive countermeasures such as evasive actions or higher temperature materials must be used to withstand or avoid this new environment.
It is an object of the present invention to provide an improved rigid, low-density insulation material.
Other objects and advantages of the present invention will be apparent to those skilled in the art.